> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vtulab.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Rate Limits

> Understanding the API usage limits on VTULab.

To ensure the stability and reliability of our platform for all users, VTULab implements rate limits on all API requests.

## Standard Limits

Rate limits are applied based on your API key and are calculated on a per-minute basis.

| Service Type                     | Rate Limit              |
| :------------------------------- | :---------------------- |
| **VTU Services** (Data, Airtime) | 60 requests per minute  |
| **Identity Services** (NIN, BVN) | 30 requests per minute  |
| **Information/Catalog** (GET)    | 120 requests per minute |

## Handling Rate Limits

When you exceed a rate limit, the API will return a `429 Too Many Requests` error.

### Headers

Our API includes headers in every response to help you track your current usage:

* `X-RateLimit-Limit`: The maximum number of requests allowed in the period.
* `X-RateLimit-Remaining`: The number of requests remaining in the current period.
* `Retry-After`: The number of seconds to wait before making another request.

### Best Practices

<CardGroup cols={2}>
  <Card title="Implement Backoff" icon="clock-rotate-left">
    Use exponential backoff in your retry logic when you receive a 429 error.
  </Card>

  <Card title="Cache Catalog Data" icon="database">
    Do not call the Data Catalog endpoint for every transaction. Cache it for at least 1 hour.
  </Card>
</CardGroup>

<Info>
  Need higher limits for a high-volume application? Contact our sales team at [sales@vtulab.com](mailto:sales@vtulab.com) to discuss custom plans.
</Info>